Oiling system for internal combustion engines



April 9, 1935. P. E. MACK OILING SYSTEM FOR INTERNAL COMBUSTION ENGINES I, e! Ferry .E. Mack Patented Apr. 9, 1935 V I I 1,996,817I ,OIL'ING SYSTEM FOR INTERNAL COMBUS- r I 'TION ENGINES I Perry E. Mack, MilwaukeegWisgj assignor to Briggs & Stratton Corporation, ,Milwaukee, Wis., a corporation of Delaware Application January 31, 1934, Serial No. 709,167

r 2 Claims.

This invention relates to certain new and useful improvements in lubricating systems for internal combustion engines, and has as an object to provide means for positively projecting a lubri- 5 cant up into the cylinder and piston to simul- Zaneously lubricate these parts and cool the pis- With the above and other objects in view which will appearas the description proceeds, my inven- 10 tion resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of 15 the herein disclosed invention, may be made as come within the scope of the claims.

In the accompanying drawing, I have illus- 2 to the best mode I have so far devised for the in which: I

The single figure is an end view of an internal combustion engine with parts broken away and 25 in section and illustrating the application of this invention thereto.

Referring now to the accompanying drawing, the numeral 5 represents generally the crank case of the engine illustrated, which rests on and is 30 closed by a base 5 adapted to hold a supply of lubricant. A cylinder block I is secured to the upper portion of the crank case with its bore 9 communicating with the interior of the case. A piston 8 operates in the bore 9 and is connected through a rod I with the crank shaft II in the customary manner. 1

Alongside the cylinder are the intake and exhaust valves of the engine, which, as iscustomary,

are operated from a cam shaft I2, disposed within 40 the crank case 5. r

In the conventional small gas engine to which this invention is particularly directed, the lubrication of the engine parts is generally accomplished by the splash system, the oil being 45 splashed up onto the operating mechanism by the connecting rod and crank shaft dipping down into the oil contained within the crank case.

While this system generally affords adequate lubrication, this invention contemplates the pro- 50 vision of means for positively supplying oil to the piston and cylinder, which are the parts most diflicult to lubricate properly by the splash system. Besides augmenting the lubrication of these parts, the present invention also simultaneously 55 effects a cooling of the piston.

practical application of the principles thereof, and

These objects are attained by providing a small force pump I 3 of any suitable construction, and located so that its intake is submerged within the oil in the crankcase. The outlet of the pump has a discharge tube I4 leading up into the vcyl- 5 inder with its discharge end I5 arranged to spray oil up into the cylinder and into the inside of the piston. g a

The pump I3 is operated by a plunger I6 projecting upwardly therefrom and guided at its upper end by a stationary guide bracket H. .The plunger I6 is located alongside the cam shaft I 2. A cross arm I 8 is secured to the plunger with I one end under the cam shaft to be engageable by a cam J9 fixed to the cam shaft, whereby reciprocation of the plunger I6 is effected during operation of the engine, a spring (not shown) within the pump, yieldably urging the plunger upwardly to maintain its arm I 8 in engagement with the cam I9. The opposite end of the cross arm has an upstanding stem 20, which is also slidably received in the guide bracket I'I to hold the plunger against turning and maintain-the cross arm in engagement with the cam I9. Y

During operation of the engine, the reciproca- '25 tion of the plunger I6, effected in the manner hereinbefore described, causes the pump I3 to draw oil from the supply within the crank case and force it outwardly from the mouth I 5 of the discharge tube I4 upwardly into the cylinder and against the under-surface of the piston. Con sequently, the cylinder Walls are positively lubricated and much of the heat developed in-the 7 piston is carried ofi.' V r I It is to be observed that the cam I9 is so fixed on the cam shaft I2 that thepump plunger I6 is moved in its compression stroke to efiect the expulsion of the lubricant from the mouth I5 only during the power stroke of the piston 8.

WhatI claim as my invention is :v

1. In' an internal combustion engine having a piston operating within a cylinder, a cam shaft and a crank case to contain a supply of lubricant, a force pump mounted within the crank case and arranged to take lubricant from the supply contained within the crank case, a discharge pipe for the force pump extending from the pump to the mouth of the cylinder to direct a spray of lubricant up into the cylinder and against the underside of the piston, and means to operate the pump from the cam shaft of the engine comprising a plunger for the pump having a part in juxtaposition to the cam shaft, a fixed guide in which the plunger is slidably received, a cross armfixed to the plunger, a stem parallel with the plunger TENT os-Pic engaging said follower to reciprocate the plunger,

and guide means to slidably receive said stem to hold the plunger against rotation and the arm in' engagement with the cam.

2. In an internal combustion engine having a piston operating within a cylinder, a cam shaft and a crank case to contain a supply of lubricant, a force pump mounted within the crank case and arranged to take lubricant from the supply contained within the crank case, a discharge pipe for the force pump extending from the pump to the mouth of the cylinder to direct a spray of lubricant up into the cylinder and against the underside of the piston, and means to operate the pump from the cam shaft comprising a cam on said cam shaft, a plunger for the pump having a portion in juxtaposition to the cam, a fixed guide in'which the plunger is slidably received to be held thereby in proper relationship to the cam, a lateral arm projecting from the plunger to engage the camasa cam follower, a second arm extending laterally from the plunger, a stem carried by said second arm in parallel relationship to the plunger, and a fixed guide to slidably receive the stem, said stem acting inits guide to hold the plunger against rotation and maintain the cam follower in engagement with the cam.

l PERRY E. MACK. 

